Sealed joint for shaft entering vessel - has coaxial flexible bellows inside and outside housing movable by shaft flange

摘要

The shaft (2) which passes through the wall (1) of a sealed vessel is required to move axially but still maintaining a perfect seal. A flexible bellows (4) connects the flange (13) on the shaft (2) to the internal flange of the housing (5). A second bellows (3) connects the flange (6) of the housing (5) to the wall (1). By using two bellows the shaft (2) is free to move a distance equal to the sum of the maximum deflections of each bellows. Also by fitting the bellows (4) inside the bellows (3) this flexibility is achieved within the axial length of a single bellows.